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Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES. Past studies were reviewed in the light of today's technical advancement and a technology trade-off, supported by bread boarding, is performed. Current activities do concentrate on Critical technology selection and feasibility demonstration including bread boarding and testing, Methane Pyrolysis Assembly (MPA) operational interfaces with ARES Potential applications of MPA for other exploration capabilities, like in-situ resources utilization (Moon and Mars) The paper presents the achievements so far.

During the last years extensive work has been done to design and develop the Closed-Loop Air Revitalization System ARES. The potential of ARES e.g. as part of the ISS ECLSS is to significantly reduce the water upload demand and to increase the safety of the crew by reducing dependence on re-supply flights. The design is adapted to the interfaces of the new base lined Russian MLM module as possible location for a future installation of ARES. Due to the lack of orbital support equipment and interfaces to a waste water bus, to a feed water supply line and due to the availability of only one single vent line it was necessary to make the ARES process water loop as independent as possible from the host vehicle. Another optimization effort was to match the CO2 desorption profile with the available hydrogen flow to achieve a sufficient water recovery performance, while meeting all related safety requirements, minimizing complexity and improving reliability.

European Space Agency (ESA) has planned two important missions for performing astronomical investigations in the infrared and sub-millimetre wavelength range: ♦Herschel satellite has an observatory type mission and is the fourth cornerstone mission (CS4) of the “Horizon 2000” programme. It will carry three instruments (HIFI, SPIRE, and PACS) for high and medium resolution spectroscopy, imaging and photometry over the sub-millimetre and far-infrared range. A 3.5 m telescope will focus the incoming radiation on the Focal Plane Units of these instruments. ♦Planck satellite has a survey type mission and is the third Medium mission (M3) of the “Horizon 2000” programme. It will provide a definitive high-angular resolution map of the cosmic microwave background anisotropies over at least 95% of the sky and over a wide frequency range. A 1.5 m telescope will focus the incoming radiation on the focal plane shared by the two instruments (LFI and HFI).

This paper describes the transient simulation of a single-phase mechanically pumped fluid loop (MPFL) thermal control system, developed in the frame of the European Space Agency ARTES 8 (Advanced Research in Telecommunication Systems - Large Platform Program) program. MPFL is intended to cool a part of the payload on a high power telecommunication satellite. A transient simulation has been implemented using ESATAN/FHTS; hence the results have been correlated with the test results, obtained from full scale MPFL testing, using real on-orbit profiles. The most considerable parts of the activities described herein are simulation of the thermal control law, verification of control parameters during thermo-hydraulic testing and the subsequent correlation.

The first use of the Polar Platform (PPF) is for the Envisat/PPF mission. The Envisat/PPF spacecraft has a launch mass of 8.5 tons and external dimensions of 10.0 metres x 2.8 metres x 2.1 metres. Due to it's large size it was necessary to perform the thermal balance and thermal vacuum testing in two modules. The first test was for the Service Module (SM) and the second for the Payload Module (PLM). This paper discusses the thermal balance testing and subsequent correlation of the Polar Platform Service Module thermal mathematical model.

An increasing number of spacecraft missions have very stringent requirements for thermal stability to avoid thermally driven noise from affecting the main observables. For example, it may be necessary to reduce temperature fluctuations in the neighbourhood of the instrument below micro-Kelvin (μK). Consequently, the influence of fluctuations in boundary temperature or internal power dissipation on temperature at the instrument detector must be precisely evaluated. Thermal stability requirements are usually expressed as an upper limit on the linear spectrum density (LSD) of temperature fluctuations. This indicates the strength of the response to a perturbation of a given frequency, and is usually stated in units of K/√Hz. The LSD can be estimated by running a succession of transient simulations and applying Fast Fourier Transforms techniques, but this method is time-consuming and has numerical limitations.

Astrium investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES, see figure 1. Past studies as presented in ref. /1/ had been reviewed in light of today's technical advancement and a technology trade-off, supported by bread boarding, resulting in the pre selection of the plasma technique to perform the Methane Pyrolysis. In parallel two methods for plasma provision are investigated: Direct Current Plasma, sustained by a discharge arc rotating in a nozzle to supply energy to the flowing through carrier gas. Micro Wave (MW) Plasma, sustained by a MW within a Quartz tube embedded in a MW resonator cuboid Study activities did concentrate on Development testing of pre selected plasma Pyrolysis technology.

The aim of this study was to explore if fingernail delamination injury following EMU glove use may be caused by compression-induced blood flow occlusion in the finger. During compression tests, finger blood flow decreased more than 60%, however this occurred more rapidly for finger pad compression (4 N) than for fingertips (10 N). A pressure bulb compression test resulted in 50% and 45% decreased blood flow at 100 mmHg and 200 mmHg, respectively. These results indicate that the finger pad pressure required to articulate stiff gloves is more likely to contribute to injury than the fingertip pressure associated with tight fitting gloves.

The Closed-Loop Air REvitalisation System ARES is a regenerative life support system for closed habitats. With regenerative processes the ARES covers the life support functions: 1. Removal of carbon dioxide from the spacecraft atmosphere via a regenerative adsorption/desorption process, 2. Supply of breathable oxygen via electrolysis of water, 3. Catalytic conversion of carbon dioxide with hydrogen to water and methane. ARES will be accommodated in a double ISPR Rack which will contain all main and support functions like power and data handling and process water management. It is foreseen to be installed onboard the International Space Station (ISS) in the Columbus Module in 2013. After an initial technology demonstration phase ARES shall continue to operate thus enhancing the capabilities of the ISS Life Support System as acknowledged by NASA [5]. Due to its regenerative processes ARES will allow a significant reduction of water upload to the ISS.

The development process of space mission software has to go through numerous steps, from early dimensioning factors at system level (e.g. energy to be consumed by a system, weight of equipment) to the description of low-level software concerns (tasks period, etc.). Most of the time, mission components are taken or derived from existing projects and use well-known best practices: hardware and software concerns are designed from a set of existing components, and are usually well tested and documented. However, teams, with different technical backgrounds, and development approaches, achieve the design. This adds incidental complexity to the design of a common architecture and its verification. Consequently, even if design of new systems is close to existing ones, the recurring key challenge is to reconcile the different views built by these teams, and to ensure that all properties are preserved and validated.

EADS SPACE Transportation investigates Methane Pyrolysis in the perspective of long-duration exploration missions. In particular this process, which recovers Hydrogen from Methane, allows reaching the maximum closure level of the Air Revitalization System ARES. Past studies are reviewed in the light of today's technical advancement and a technology trade-off, supported by breadboarding, is performed. Accordingly, current activities do concentrate on Critical technology selection and feasibility demonstration including breadboarding and testing, Methane Pyrolysis Assembly (MPA) operational interfaces with ARES Potential applications of MPA for other exploration capabilities, like in-situ resources utilization (Moon and Mars) The paper presents the achievements so far.

ESARAD is an integrated suite of analysis tools for thermal radiative analysis. The suite provides modules for: • Geometry Definition; • Calculation of view factor, radiative exchange factor and solar, albedo and planet flux results; •Visualization of models in orbit with pre- and post-processing of radiative and thermal results; • Reporting of all aspects of the model; and • Generation of Input Files for Thermal Analysis tools. ESARAD is driven by a fully developed GUI, providing the user with a simple, intuitive windows, menus, forms interface to all its features. A modern, block structured language can also be used to run ESARAD. This gives the advanced user great power and flexibility to perform the most complex analyses. ESARAD was designed and developed between 1988 and 1991 to replace the VWHEAT software used by ESA at that time.

The Columbus Orbital Facility is being developed as the European laboratory contribution to the United States' led International Space Station programme. The need to exchange thermal mathematical models frequently amongst the Space Station partners for thermal analyses in support of their individual programme milestone, integration and verification activities requires the development of a commonly agreed and effective approach to identify and validate mathematical models and environments. The approach needs to take into account the fact that the partners have different model and software tool requirements and the fact that the models need to be properly tailored to include all the relevant design features. It must also decouple both programmes from the unavoidable design changes they are still undergoing. This problem presents itself for both active and passive thermal interfaces.

This paper describes recent advances in MPB's approach to spacecraft thermal control based on a passive thin-film smart radiator tile (SRT) that employs a variable heat-transfer/emitter structure. This can be applied to Al thermal radiators as a direct replacement for the existing OSR (optical second-reflector) radiator tiles with a net added mass under 100 gm/m2. The SRT employs a smart, integrated thin-film structure based on the nano-engineering of V1-x-yMxNyOn that facilitates thermal control by dynamically modifying the net infrared emittance passively in response to the temperature of the space structure. Dopants, M and N, are employed to tailor the transition temperature characteristics of the tuneable IR emittance. This facilitates thermal emissivities below 0.3 to dark space at lower temperatures that enhance the self-heating of the spacecraft to reduce heater requirements.

A final test activity was carried out to complete the verification of the Environmental Control System (ECS) performances by experimentally reproducing the thermal hydraulic behaviour of the Environmental Control & Life Support Subsystem (ECLSS) section integrated in the overall Module, expected on analytical basis. A previous test campaign (called Columbus ECS PFM Test) carried out in EADS-Bremen in spring 2003 and described in paper number 2004-01-2425 showed some contradictory data concerning the air loop behaviour. These incoherent test results were related to the environmental and geometrical cabin loop conditions during the on-ground 1g test and to improper position of the sensor measuring the cabin temperature. For this reason a partial repetition of the test has been performed. In particular, this experimental campaign was focused on the verification of the cabin air temperature control, as a consequence of the Temperature Control Valve (TCV) movement.

The Columbus ECS PFM Test was intended as the final verification of the Module Thermal Design after a series of successful tests at subsystems level (e.g. the Active Thermal Control Subsystem and the Environmental Control and Life Support System) The test campaign has been articulated as a sequence of several test cases to investigate the main thermal aspects, to prove the Module thermal design in the extreme operative conditions and to correlate the thermal mathematical model (TMM). The interpretation of test results and the correlation confirmed that the thermal design of the module is adequate, but some areas of concern remain, mainly for the difficulty to translate to 0-g the results of a complex test in 1-g environment, and for some aspects of the air and cabin loops.

The Automated Transfer Vehicle (ATV) Thermal Control System (TCS) has the task to ensure the required internal environment at level of pressurized module and to thermally control the not pressurised modules and installed equipment, using passive and active control means, in response to the relevant applicable requirements. The ATV vehicle is assially subdivided into three main modules: the Integrated Cargo Carrier (ICC), the Equipped Avionics Bay (EAB) and the Equipped Propulsion Bay (EPB). Each of these modules present elaborated and specific thermal design solutions, to satisfy the different required operative tasks. The extensive thermal analysis campaign performed at ATV vehicle level and in progress for the next Qualification Review (QR) to justify and support the thermal control design solutions and verification status is described.

Given the constraints of the current launchers, manned exploration beyond LEO implies long time missions, a high mass of metabolic consumables and consequently regenerative life support technologies developments. To validate their efficiency, as well as their reliability, these technologies need to be tested in the most analog conditions (i.e. isolation, limited spare part, …). A large number of these conditions are met in the new permanent French-Italian settlement called Concordia, currently being built in the Antarctic continent. Over the last 15 years, ESA developed regenerative life support technologies. Two of these technologies: a Grey Water Treatment Unit and a Black Water Treatment Unit are currently assembled at the size of 15 to 70 persons to fulfill the Concordia crew needs The first technology is a multi step filtration system and will recycle the shower, washing machine, dish washer and cleaning water.

For the last 10 years, ESA has initiated Life Support activities to prepare long-term manned missions. Although a large part of these activities were based on physico-chemical technologies, biological processes were considered as well. A few projects were initiated: air contaminants removal (e.g. BAF) up to the complete and complex approach of artificial ecosystems (e.g. MELISSA). In order to make a complete survey of the existing developments, to evaluate their advantages and weaknesses, to identify the needs of future projects, as well as to understand the interest of industry, an Advanced Life Support Workshop has been organised in April 1999 by ESA. This paper reviews the existing developments and presents the recommendations of the workshop. A specific part is devoted to the projects in collaboration with the ESA Life Sciences community and the results of the 1999 announcement of opportunity, which included Biological life Support.

1 The Closed-Loop Air REvitalisation System ARES is a proof of technology Payload. The objective of ARES is to demonstrate with regenerative processes: the provision of the capability for carbon dioxide removal from the module atmosphere, the return supply of breathable oxygen within a closed-loop process, the conversion of the hydrogen, resulting from the oxygen generation via electrolysis, to water. The ARES Payload is foreseen to be installed - in 2012 - onboard the ISS in the Columbus Module. The operation of ARES - in a representative manned microgravity environment - will produce valuable operational data on a system which is based on technologies which are different from other air revitalization systems presently in use. The ARES Technology Demonstrator Payload development started in 2003 with a Phase B, see references [1], [2], [3] and [4]. ARES is presently in Phase C1 and a PDR is scheduled for the beginning of 2009.